Online Computer Terms Dictionary - P

portmapper

<networking> A server that converts TCP/IP protocol port numbers into RPC
program numbers. It must be running in order to make RPC calls.

When an RPC server starts, it tells portmap the port number it is listening on
and what RPC program numbers it serves. Before a client can call a given RPC
program number, it must contacts portmap on the server machine to determine the
port number to which RPC packets should be sent.